Popular belief has it that the term Balisong is derived from the Tagalog words baling sungay (meaning, “broken or folding horn”). These knives, were originally crafted from stag horn and carved carabao in the town of Taal, Bantangas province and named after a Barangay.
Sometimes called viente y nueve (or Spanish for the number 29) the traditional Balison is 29 centimeters in length when fully opened.

The unusual action of opening the butterfly knife by flipping, turning, and fanning causes a “click clack” sound in the process of being opened and closed. DiscountKnivesAndSwords.com has many popular butterfly knives for sale.
The art of the Butterfly knife is to learn the technique of “flipping” or “fanning” the two handled knife with a single hand.
Also known as a Balisong or fan knife, this folding pocket knife counter rotates around the tang so that the blade resides concealed inside the grooved handle.

Traditionally made in the Tagalong region of Batangas in the Philippines, the native Filipios used the butterfly knife as self defense and as a utility pocket knife.
When workers found it inconvenient to use two hands to open a knife, the Balisongs became very popular because of of the ease of opening the Butterfly knife Butterfly knife with a single hand. Additionally, Balisongs were originally used as a straight razor before conventional razors were introduced to the Philippines.